53 Aquarii

53 Aquarii
Diagram showing star positions and boundaries of the Aquarius constellation and its surroundings


Location of 53 Aquarii (circled)

Observation data
Epoch J2000      Equinox J2000
Constellation Aquarius
Right ascension 22h 26m 34.2753s[1]
Declination –16° 44′ 31.697″[1]
Apparent magnitude (V) 5.56[2] (6.35/6.57)[3]
Characteristics
Spectral type G1 V + G5 V Fe–0.8 CH–1[4]
U−B color index +0.09[2]
B−V color index +0.61[2]
Astrometry
Radial velocity (Rv)+2.1[5] km/s
Proper motion (μ) RA: +200.59[1] mas/yr
Dec.: +14.51[1] mas/yr
Parallax (π)49.50 ± 1.23[1] mas
Distance66 ± 2 ly
(20.2 ± 0.5 pc)
Absolute magnitude (MV)4.05[5] (4.94/4.87)[3]
Details
53 Aqr A
Mass0.99[6] M☉
Radius1.11[6] R☉
Luminosity1.39[6] L☉
Surface gravity (log g)4.46[3] cgs
Temperature5,922[3] K
Metallicity [Fe/H]–0.10[3] dex
Rotational velocity (v sin i)8[7] km/s
Age0.18–0.37[8] Gyr
53 Aqr B
Surface gravity (log g)4.44[3] cgs
Temperature5,811[3] K
Metallicity [Fe/H]–0.19[3] dex
Rotational velocity (v sin i)9[7] km/s
Other designations
f Aquarii, GJ 859, HIP 110778.[9]
53 Aqr A: BD–17 6521, HD 212698, HR 8545, LTT 9026, SAO 165078.
53 Aqr B: BD–17 6520, HD 212697, HR 8544, LTT 9025, SAO 165077.

53 Aquarii is the Flamsteed designation for a binary star [10] system in the equatorial constellation of Aquarius. The combined apparent visual magnitude of the pair is a 5.56,[2] making it just visible to the naked eye in dark suburban skies. Based upon an annual parallax shift of 49.50 milliarcseconds for the first component, this system is located at a distance of approximately 65 light-years (20 parsecs) from Earth.[1]

This is a wide binary star system with a projected separation of 100 astronomical units; indicating that the two stars are at least this distance apart.[6] The primary component is a solar-type main sequence star with a stellar classification of G1 V.[4] It has about 99% of the Sun's mass, 111% of the Sun's radius, and shines with 139% of the luminosity of the Sun.[6] This energy is being emitted from an outer envelope at an effective temperature of 5,922 K,[3] giving it the golden hue of a G-type star.[11] An examination of the primary component with the Spitzer space telescope failed to detect any infrared excess that might otherwise be an indication of a circumstellar debris disk.[6]

The companion is a slightly cooler star with an effective temperature of 5,811 K.[3] It has a stellar classification of G5 V Fe–0.8 CH–1,[4] indicating it is a chemically peculiar G-type main sequence star showing an under-abundance of iron and the molecule CH in its spectrum. As of 2008, it has an angular separation of 1.325 arcseconds along a position angle of 30.9° from the primary.[12]

This system is coeval with the Castor Moving Group of stars that share a common motion through space; hence it is a candidate member of that association. This suggests that the system is young; its estimated age is in the range of 180 to 370 million years, based upon the spectrum and X-ray luminosity, respectively.[8]

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357.
  2. ↑ 2.0 2.1 2.2 2.3 Nicolet, B. (1978), "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System", Astronomy and Astrophysics Supplement Series 34: 1–49, Bibcode:1978A&AS...34....1N.
  3. ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 Pasquini, L.; Liu, Q.; Pallavicini, R. (July 1994), "Lithium abundances of nearby solar-like stars", Astronomy and Astrophysics 287 (1): 191–205, Bibcode:1994A&A...287..191P.
  4. ↑ 4.0 4.1 4.2 Gray, R. O. et al. (July 2006), "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 parsecs: The Northern Sample I", The Astronomical Journal 132 (1): 161–170, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637.
  5. ↑ 5.0 5.1 Nordström, B. et al. (May 2004), "The Geneva-Copenhagen survey of the Solar neighbourhood. Ages, metallicities, and kinematic properties of ˜14 000 F and G dwarfs", Astronomy and Astrophysics 418: 989–1019, arXiv:astro-ph/0405198, Bibcode:2004A&A...418..989N, doi:10.1051/0004-6361:20035959.
  6. ↑ 6.0 6.1 6.2 6.3 6.4 6.5 Plavchan, Peter et al. (June 2009), "New Debris Disks Around Young, Low-Mass Stars Discovered with the Spitzer Space Telescope", The Astrophysical Journal 698 (2): 1068–1094, arXiv:0904.0819, Bibcode:2009ApJ...698.1068P, doi:10.1088/0004-637X/698/2/1068.
  7. ↑ 7.0 7.1 Torres, C. A. O. et al. (December 2006), "Search for associations containing young stars (SACY). I. Sample and searching method", Astronomy and Astrophysics 460 (3): 695–708, arXiv:astro-ph/0609258, Bibcode:2006A&A...460..695T, doi:10.1051/0004-6361:20065602.
  8. ↑ 8.0 8.1 Maldonado, J. et al. (October 2010), "A spectroscopy study of nearby late-type stars, possible members of stellar kinematic groups", Astronomy and Astrophysics 521: A12, arXiv:1007.1132, Bibcode:2010A&A...521A..12M, doi:10.1051/0004-6361/201014948.
  9. ↑ "53 Aqr -- Double or multiple star", SIMBAD Astronomical Object Database (Centre de Données astronomiques de Strasbourg), retrieved 2012-07-14. See also the children entries.
  10. ↑ Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society 389 (2): 869–879. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x.
  11. ↑ "The Colour of Stars", Australia Telescope, Outreach and Education (Commonwealth Scientific and Industrial Research Organisation), December 21, 2004, retrieved 2012-01-16.
  12. ↑ Tokovinin, A.; Cantarutti, R. (February 2008), "First Speckle Interferometry at SOAR Telescope with Electron-Multiplication CCD", Publications of the Astronomical Society of the Pacific 120 (864): 170–177, Bibcode:2008PASP..120..170T, doi:10.1086/528809.